Materials Data on MgAlB4 by Materials Project
MgAlB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Mg is bonded to twelve equivalent B atoms to form MgB12 cuboctahedra that share edges with twelve equivalent AlB12 cuboctahedra, faces with two equivalent AlB12 cuboctahedra, and faces with six equivalent MgB12 cuboctahedra. All Mg–B bond lengths are 2.51 Å. Al is bonded to twelve equivalent B atoms to form AlB12 cuboctahedra that share edges with twelve equivalent MgB12 cuboctahedra, faces with two equivalent MgB12 cuboctahedra, and faces with six equivalent AlB12 cuboctahedra. All Al–B bond lengths are 2.36 Å. B is bonded in a 9-coordinate geometry to three equivalent Mg, three equivalent Al, and three equivalent B atoms. All B–B bond lengths are 1.75 Å.